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  <div class="section" id="object-protocol">
<span id="object"></span><h1>Object Protocol<a class="headerlink" href="#object-protocol" title="Permalink to this headline">¶</a></h1>
<dl class="var">
<dt id="c.Py_NotImplemented">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">Py_NotImplemented</code><a class="headerlink" href="#c.Py_NotImplemented" title="Permalink to this definition">¶</a></dt>
<dd><p>The <code class="docutils literal"><span class="pre">NotImplemented</span></code> singleton, used to signal that an operation is
not implemented for the given type combination.</p>
</dd></dl>

<dl class="macro">
<dt id="c.Py_RETURN_NOTIMPLEMENTED">
<code class="descname">Py_RETURN_NOTIMPLEMENTED</code><a class="headerlink" href="#c.Py_RETURN_NOTIMPLEMENTED" title="Permalink to this definition">¶</a></dt>
<dd><p>Properly handle returning <a class="reference internal" href="#c.Py_NotImplemented" title="Py_NotImplemented"><code class="xref c c-data docutils literal"><span class="pre">Py_NotImplemented</span></code></a> from within a C
function (that is, increment the reference count of NotImplemented and
return it).</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Print">
int <code class="descname">PyObject_Print</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, FILE<em>&nbsp;*fp</em>, int<em>&nbsp;flags</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Print" title="Permalink to this definition">¶</a></dt>
<dd><p>Print an object <em>o</em>, on file <em>fp</em>.  Returns <code class="docutils literal"><span class="pre">-1</span></code> on error.  The flags argument
is used to enable certain printing options.  The only option currently supported
is <code class="xref py py-const docutils literal"><span class="pre">Py_PRINT_RAW</span></code>; if given, the <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-func docutils literal"><span class="pre">str()</span></code></a> of the object is written
instead of the <a class="reference internal" href="../library/functions.html#repr" title="repr"><code class="xref py py-func docutils literal"><span class="pre">repr()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_HasAttr">
int <code class="descname">PyObject_HasAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HasAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <code class="docutils literal"><span class="pre">1</span></code> if <em>o</em> has the attribute <em>attr_name</em>, and <code class="docutils literal"><span class="pre">0</span></code> otherwise.  This
is equivalent to the Python expression <code class="docutils literal"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></code>.  This function
always succeeds.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_HasAttrString">
int <code class="descname">PyObject_HasAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, const char<em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HasAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <code class="docutils literal"><span class="pre">1</span></code> if <em>o</em> has the attribute <em>attr_name</em>, and <code class="docutils literal"><span class="pre">0</span></code> otherwise.  This
is equivalent to the Python expression <code class="docutils literal"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></code>.  This function
always succeeds.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GetAttr">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetAttr" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute
value on success, or <em>NULL</em> on failure.  This is the equivalent of the Python
expression <code class="docutils literal"><span class="pre">o.attr_name</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GetAttrString">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, const char<em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetAttrString" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute
value on success, or <em>NULL</em> on failure. This is the equivalent of the Python
expression <code class="docutils literal"><span class="pre">o.attr_name</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GenericGetAttr">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GenericGetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericGetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Generic attribute getter function that is meant to be put into a type
object’s <code class="docutils literal"><span class="pre">tp_getattro</span></code> slot.  It looks for a descriptor in the dictionary
of classes in the object’s MRO as well as an attribute in the object’s
<a class="reference internal" href="../library/stdtypes.html#object.__dict__" title="object.__dict__"><code class="xref py py-attr docutils literal"><span class="pre">__dict__</span></code></a> (if present).  As outlined in <a class="reference internal" href="../reference/datamodel.html#descriptors"><span class="std std-ref">Implementing Descriptors</span></a>,
data descriptors take preference over instance attributes, while non-data
descriptors don’t.  Otherwise, an <a class="reference internal" href="../library/exceptions.html#AttributeError" title="AttributeError"><code class="xref py py-exc docutils literal"><span class="pre">AttributeError</span></code></a> is raised.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_SetAttr">
int <code class="descname">PyObject_SetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*attr_name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value
<em>v</em>. Raise an exception and return <code class="docutils literal"><span class="pre">-1</span></code> on failure;
return <code class="docutils literal"><span class="pre">0</span></code> on success.  This is the equivalent of the Python statement
<code class="docutils literal"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p>
<p>If <em>v</em> is <em>NULL</em>, the attribute is deleted, however this feature is
deprecated in favour of using <a class="reference internal" href="#c.PyObject_DelAttr" title="PyObject_DelAttr"><code class="xref c c-func docutils literal"><span class="pre">PyObject_DelAttr()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_SetAttrString">
int <code class="descname">PyObject_SetAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, const char<em>&nbsp;*attr_name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value
<em>v</em>. Raise an exception and return <code class="docutils literal"><span class="pre">-1</span></code> on failure;
return <code class="docutils literal"><span class="pre">0</span></code> on success.  This is the equivalent of the Python statement
<code class="docutils literal"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p>
<p>If <em>v</em> is <em>NULL</em>, the attribute is deleted, however this feature is
deprecated in favour of using <a class="reference internal" href="#c.PyObject_DelAttrString" title="PyObject_DelAttrString"><code class="xref c c-func docutils literal"><span class="pre">PyObject_DelAttrString()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GenericSetAttr">
int <code class="descname">PyObject_GenericSetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*value</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericSetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Generic attribute setter and deleter function that is meant
to be put into a type object’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_setattro" title="PyTypeObject.tp_setattro"><code class="xref c c-member docutils literal"><span class="pre">tp_setattro</span></code></a>
slot.  It looks for a data descriptor in the
dictionary of classes in the object’s MRO, and if found it takes preference
over setting or deleting the attribute in the instance dictionary. Otherwise, the
attribute is set or deleted in the object’s <a class="reference internal" href="../library/stdtypes.html#object.__dict__" title="object.__dict__"><code class="xref py py-attr docutils literal"><span class="pre">__dict__</span></code></a> (if present).
On success, <code class="docutils literal"><span class="pre">0</span></code> is returned, otherwise an <a class="reference internal" href="../library/exceptions.html#AttributeError" title="AttributeError"><code class="xref py py-exc docutils literal"><span class="pre">AttributeError</span></code></a>
is raised and <code class="docutils literal"><span class="pre">-1</span></code> is returned.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_DelAttr">
int <code class="descname">PyObject_DelAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <code class="docutils literal"><span class="pre">-1</span></code> on failure.
This is the equivalent of the Python statement <code class="docutils literal"><span class="pre">del</span> <span class="pre">o.attr_name</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_DelAttrString">
int <code class="descname">PyObject_DelAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, const char<em>&nbsp;*attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <code class="docutils literal"><span class="pre">-1</span></code> on failure.
This is the equivalent of the Python statement <code class="docutils literal"><span class="pre">del</span> <span class="pre">o.attr_name</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GenericGetDict">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GenericGetDict</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, void<em>&nbsp;*context</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericGetDict" title="Permalink to this definition">¶</a></dt>
<dd><p>A generic implementation for the getter of a <code class="docutils literal"><span class="pre">__dict__</span></code> descriptor. It
creates the dictionary if necessary.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GenericSetDict">
int <code class="descname">PyObject_GenericSetDict</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, void<em>&nbsp;*context</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericSetDict" title="Permalink to this definition">¶</a></dt>
<dd><p>A generic implementation for the setter of a <code class="docutils literal"><span class="pre">__dict__</span></code> descriptor. This
implementation does not allow the dictionary to be deleted.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_RichCompare">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_RichCompare</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o2</em>, int<em>&nbsp;opid</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_RichCompare" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>,
which must be one of <code class="xref py py-const docutils literal"><span class="pre">Py_LT</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_LE</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></code>,
<code class="xref py py-const docutils literal"><span class="pre">Py_NE</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_GT</span></code>, or <code class="xref py py-const docutils literal"><span class="pre">Py_GE</span></code>, corresponding to <code class="docutils literal"><span class="pre">&lt;</span></code>,
<code class="docutils literal"><span class="pre">&lt;=</span></code>, <code class="docutils literal"><span class="pre">==</span></code>, <code class="docutils literal"><span class="pre">!=</span></code>, <code class="docutils literal"><span class="pre">&gt;</span></code>, or <code class="docutils literal"><span class="pre">&gt;=</span></code> respectively. This is the equivalent of
the Python expression <code class="docutils literal"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></code>, where <code class="docutils literal"><span class="pre">op</span></code> is the operator corresponding
to <em>opid</em>. Returns the value of the comparison on success, or <em>NULL</em> on failure.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_RichCompareBool">
int <code class="descname">PyObject_RichCompareBool</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o2</em>, int<em>&nbsp;opid</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_RichCompareBool" title="Permalink to this definition">¶</a></dt>
<dd><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>,
which must be one of <code class="xref py py-const docutils literal"><span class="pre">Py_LT</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_LE</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></code>,
<code class="xref py py-const docutils literal"><span class="pre">Py_NE</span></code>, <code class="xref py py-const docutils literal"><span class="pre">Py_GT</span></code>, or <code class="xref py py-const docutils literal"><span class="pre">Py_GE</span></code>, corresponding to <code class="docutils literal"><span class="pre">&lt;</span></code>,
<code class="docutils literal"><span class="pre">&lt;=</span></code>, <code class="docutils literal"><span class="pre">==</span></code>, <code class="docutils literal"><span class="pre">!=</span></code>, <code class="docutils literal"><span class="pre">&gt;</span></code>, or <code class="docutils literal"><span class="pre">&gt;=</span></code> respectively. Returns <code class="docutils literal"><span class="pre">-1</span></code> on error,
<code class="docutils literal"><span class="pre">0</span></code> if the result is false, <code class="docutils literal"><span class="pre">1</span></code> otherwise. This is the equivalent of the
Python expression <code class="docutils literal"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></code>, where <code class="docutils literal"><span class="pre">op</span></code> is the operator corresponding to
<em>opid</em>.</p>
</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">If <em>o1</em> and <em>o2</em> are the same object, <a class="reference internal" href="#c.PyObject_RichCompareBool" title="PyObject_RichCompareBool"><code class="xref c c-func docutils literal"><span class="pre">PyObject_RichCompareBool()</span></code></a>
will always return <code class="docutils literal"><span class="pre">1</span></code> for <code class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></code> and <code class="docutils literal"><span class="pre">0</span></code> for <code class="xref py py-const docutils literal"><span class="pre">Py_NE</span></code>.</p>
</div>
<dl class="function">
<dt id="c.PyObject_Repr">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Repr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Repr" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-0">Compute a string representation of object <em>o</em>.  Returns the string
representation on success, <em>NULL</em> on failure.  This is the equivalent of the
Python expression <code class="docutils literal"><span class="pre">repr(o)</span></code>.  Called by the <a class="reference internal" href="../library/functions.html#repr" title="repr"><code class="xref py py-func docutils literal"><span class="pre">repr()</span></code></a> built-in function.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span>This function now includes a debug assertion to help ensure that it
does not silently discard an active exception.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_ASCII">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_ASCII</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_ASCII" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-1">As <a class="reference internal" href="#c.PyObject_Repr" title="PyObject_Repr"><code class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></code></a>, compute a string representation of object <em>o</em>, but
escape the non-ASCII characters in the string returned by
<a class="reference internal" href="#c.PyObject_Repr" title="PyObject_Repr"><code class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></code></a> with <code class="docutils literal"><span class="pre">\x</span></code>, <code class="docutils literal"><span class="pre">\u</span></code> or <code class="docutils literal"><span class="pre">\U</span></code> escapes.  This generates
a string similar to that returned by <a class="reference internal" href="#c.PyObject_Repr" title="PyObject_Repr"><code class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></code></a> in Python 2.
Called by the <a class="reference internal" href="../library/functions.html#ascii" title="ascii"><code class="xref py py-func docutils literal"><span class="pre">ascii()</span></code></a> built-in function.</p>
<span class="target" id="index-2"></span></dd></dl>

<dl class="function">
<dt id="c.PyObject_Str">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Str</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Str" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Compute a string representation of object <em>o</em>.  Returns the string
representation on success, <em>NULL</em> on failure.  This is the equivalent of the
Python expression <code class="docutils literal"><span class="pre">str(o)</span></code>.  Called by the <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-func docutils literal"><span class="pre">str()</span></code></a> built-in function
and, therefore, by the <a class="reference internal" href="../library/functions.html#print" title="print"><code class="xref py py-func docutils literal"><span class="pre">print()</span></code></a> function.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span>This function now includes a debug assertion to help ensure that it
does not silently discard an active exception.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Bytes">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Bytes</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Bytes" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-3">Compute a bytes representation of object <em>o</em>.  <em>NULL</em> is returned on
failure and a bytes object on success.  This is equivalent to the Python
expression <code class="docutils literal"><span class="pre">bytes(o)</span></code>, when <em>o</em> is not an integer.  Unlike <code class="docutils literal"><span class="pre">bytes(o)</span></code>,
a TypeError is raised when <em>o</em> is an integer instead of a zero-initialized
bytes object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_IsSubclass">
int <code class="descname">PyObject_IsSubclass</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*derived</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*cls</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsSubclass" title="Permalink to this definition">¶</a></dt>
<dd><p>Return <code class="docutils literal"><span class="pre">1</span></code> if the class <em>derived</em> is identical to or derived from the class
<em>cls</em>, otherwise return <code class="docutils literal"><span class="pre">0</span></code>.  In case of an error, return <code class="docutils literal"><span class="pre">-1</span></code>.</p>
<p>If <em>cls</em> is a tuple, the check will be done against every entry in <em>cls</em>.
The result will be <code class="docutils literal"><span class="pre">1</span></code> when at least one of the checks returns <code class="docutils literal"><span class="pre">1</span></code>,
otherwise it will be <code class="docutils literal"><span class="pre">0</span></code>.</p>
<p>If <em>cls</em> has a <a class="reference internal" href="../reference/datamodel.html#class.__subclasscheck__" title="class.__subclasscheck__"><code class="xref py py-meth docutils literal"><span class="pre">__subclasscheck__()</span></code></a> method, it will be called to
determine the subclass status as described in <span class="target" id="index-4"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-3119"><strong>PEP 3119</strong></a>.  Otherwise,
<em>derived</em> is a subclass of <em>cls</em> if it is a direct or indirect subclass,
i.e. contained in <code class="docutils literal"><span class="pre">cls.__mro__</span></code>.</p>
<p>Normally only class objects, i.e. instances of <a class="reference internal" href="../library/functions.html#type" title="type"><code class="xref py py-class docutils literal"><span class="pre">type</span></code></a> or a derived
class, are considered classes.  However, objects can override this by having
a <code class="xref py py-attr docutils literal"><span class="pre">__bases__</span></code> attribute (which must be a tuple of base classes).</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_IsInstance">
int <code class="descname">PyObject_IsInstance</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*inst</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*cls</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsInstance" title="Permalink to this definition">¶</a></dt>
<dd><p>Return <code class="docutils literal"><span class="pre">1</span></code> if <em>inst</em> is an instance of the class <em>cls</em> or a subclass of
<em>cls</em>, or <code class="docutils literal"><span class="pre">0</span></code> if not.  On error, returns <code class="docutils literal"><span class="pre">-1</span></code> and sets an exception.</p>
<p>If <em>cls</em> is a tuple, the check will be done against every entry in <em>cls</em>.
The result will be <code class="docutils literal"><span class="pre">1</span></code> when at least one of the checks returns <code class="docutils literal"><span class="pre">1</span></code>,
otherwise it will be <code class="docutils literal"><span class="pre">0</span></code>.</p>
<p>If <em>cls</em> has a <a class="reference internal" href="../reference/datamodel.html#class.__instancecheck__" title="class.__instancecheck__"><code class="xref py py-meth docutils literal"><span class="pre">__instancecheck__()</span></code></a> method, it will be called to
determine the subclass status as described in <span class="target" id="index-5"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-3119"><strong>PEP 3119</strong></a>.  Otherwise, <em>inst</em>
is an instance of <em>cls</em> if its class is a subclass of <em>cls</em>.</p>
<p>An instance <em>inst</em> can override what is considered its class by having a
<code class="xref py py-attr docutils literal"><span class="pre">__class__</span></code> attribute.</p>
<p>An object <em>cls</em> can override if it is considered a class, and what its base
classes are, by having a <code class="xref py py-attr docutils literal"><span class="pre">__bases__</span></code> attribute (which must be a tuple
of base classes).</p>
</dd></dl>

<dl class="function">
<dt id="c.PyCallable_Check">
int <code class="descname">PyCallable_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyCallable_Check" title="Permalink to this definition">¶</a></dt>
<dd><p>Determine if the object <em>o</em> is callable.  Return <code class="docutils literal"><span class="pre">1</span></code> if the object is callable
and <code class="docutils literal"><span class="pre">0</span></code> otherwise.  This function always succeeds.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Call">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Call</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*callable_object</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*args</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*kw</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Call" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable_object</em>, with arguments given by the
tuple <em>args</em>, and named arguments given by the dictionary <em>kw</em>. If no named
arguments are needed, <em>kw</em> may be <em>NULL</em>. <em>args</em> must not be <em>NULL</em>, use an
empty tuple if no arguments are needed. Returns the result of the call on
success, or <em>NULL</em> on failure.  This is the equivalent of the Python expression
<code class="docutils literal"><span class="pre">callable_object(*args,</span> <span class="pre">**kw)</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_CallObject">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*callable_object</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*args</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable_object</em>, with arguments given by the
tuple <em>args</em>.  If no arguments are needed, then <em>args</em> may be <em>NULL</em>.  Returns
the result of the call on success, or <em>NULL</em> on failure.  This is the equivalent
of the Python expression <code class="docutils literal"><span class="pre">callable_object(*args)</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_CallFunction">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallFunction</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*callable</em>, const char<em>&nbsp;*format</em>, ...<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFunction" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable</em>, with a variable number of C arguments.
The C arguments are described using a <a class="reference internal" href="arg.html#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal"><span class="pre">Py_BuildValue()</span></code></a> style format
string.  The format may be <em>NULL</em>, indicating that no arguments are provided.
Returns the result of the call on success, or <em>NULL</em> on failure.  This is the
equivalent of the Python expression <code class="docutils literal"><span class="pre">callable(*args)</span></code>. Note that if you only
pass <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal"><span class="pre">PyObject</span> <span class="pre">*</span></code></a> args, <a class="reference internal" href="#c.PyObject_CallFunctionObjArgs" title="PyObject_CallFunctionObjArgs"><code class="xref c c-func docutils literal"><span class="pre">PyObject_CallFunctionObjArgs()</span></code></a> is a
faster alternative.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span>The type of <em>format</em> was changed from <code class="docutils literal"><span class="pre">char</span> <span class="pre">*</span></code>.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_CallMethod">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallMethod</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, const char<em>&nbsp;*method</em>, const char<em>&nbsp;*format</em>, ...<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallMethod" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call the method named <em>method</em> of object <em>o</em> with a variable number of C
arguments.  The C arguments are described by a <a class="reference internal" href="arg.html#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal"><span class="pre">Py_BuildValue()</span></code></a> format
string that should  produce a tuple.  The format may be <em>NULL</em>, indicating that
no arguments are provided. Returns the result of the call on success, or <em>NULL</em>
on failure.  This is the equivalent of the Python expression <code class="docutils literal"><span class="pre">o.method(args)</span></code>.
Note that if you only pass <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal"><span class="pre">PyObject</span> <span class="pre">*</span></code></a> args,
<a class="reference internal" href="#c.PyObject_CallMethodObjArgs" title="PyObject_CallMethodObjArgs"><code class="xref c c-func docutils literal"><span class="pre">PyObject_CallMethodObjArgs()</span></code></a> is a faster alternative.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span>The types of <em>method</em> and <em>format</em> were changed from <code class="docutils literal"><span class="pre">char</span> <span class="pre">*</span></code>.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_CallFunctionObjArgs">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallFunctionObjArgs</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*callable</em>, ..., NULL<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFunctionObjArgs" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable</em>, with a variable number of
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal"><span class="pre">PyObject*</span></code></a> arguments.  The arguments are provided as a variable number
of parameters followed by <em>NULL</em>. Returns the result of the call on success, or
<em>NULL</em> on failure.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_CallMethodObjArgs">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallMethodObjArgs</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*name</em>, ..., NULL<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallMethodObjArgs" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Calls a method of the object <em>o</em>, where the name of the method is given as a
Python string object in <em>name</em>.  It is called with a variable number of
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal"><span class="pre">PyObject*</span></code></a> arguments.  The arguments are provided as a variable number
of parameters followed by <em>NULL</em>. Returns the result of the call on success, or
<em>NULL</em> on failure.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Hash">
Py_hash_t <code class="descname">PyObject_Hash</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Hash" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-6">Compute and return the hash value of an object <em>o</em>.  On failure, return <code class="docutils literal"><span class="pre">-1</span></code>.
This is the equivalent of the Python expression <code class="docutils literal"><span class="pre">hash(o)</span></code>.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.2: </span>The return type is now Py_hash_t.  This is a signed integer the same size
as Py_ssize_t.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_HashNotImplemented">
Py_hash_t <code class="descname">PyObject_HashNotImplemented</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HashNotImplemented" title="Permalink to this definition">¶</a></dt>
<dd><p>Set a <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal"><span class="pre">TypeError</span></code></a> indicating that <code class="docutils literal"><span class="pre">type(o)</span></code> is not hashable and return <code class="docutils literal"><span class="pre">-1</span></code>.
This function receives special treatment when stored in a <code class="docutils literal"><span class="pre">tp_hash</span></code> slot,
allowing a type to explicitly indicate to the interpreter that it is not
hashable.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_IsTrue">
int <code class="descname">PyObject_IsTrue</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsTrue" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <code class="docutils literal"><span class="pre">1</span></code> if the object <em>o</em> is considered to be true, and <code class="docutils literal"><span class="pre">0</span></code> otherwise.
This is equivalent to the Python expression <code class="docutils literal"><span class="pre">not</span> <span class="pre">not</span> <span class="pre">o</span></code>.  On failure, return
<code class="docutils literal"><span class="pre">-1</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Not">
int <code class="descname">PyObject_Not</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Not" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <code class="docutils literal"><span class="pre">0</span></code> if the object <em>o</em> is considered to be true, and <code class="docutils literal"><span class="pre">1</span></code> otherwise.
This is equivalent to the Python expression <code class="docutils literal"><span class="pre">not</span> <span class="pre">o</span></code>.  On failure, return
<code class="docutils literal"><span class="pre">-1</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Type">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Type</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Type" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-7">When <em>o</em> is non-<em>NULL</em>, returns a type object corresponding to the object type
of object <em>o</em>. On failure, raises <a class="reference internal" href="../library/exceptions.html#SystemError" title="SystemError"><code class="xref py py-exc docutils literal"><span class="pre">SystemError</span></code></a> and returns <em>NULL</em>.  This
is equivalent to the Python expression <code class="docutils literal"><span class="pre">type(o)</span></code>. This function increments the
reference count of the return value. There’s really no reason to use this
function instead of the common expression <code class="docutils literal"><span class="pre">o-&gt;ob_type</span></code>, which returns a
pointer of type <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal"><span class="pre">PyTypeObject*</span></code></a>, except when the incremented reference
count is needed.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_TypeCheck">
int <code class="descname">PyObject_TypeCheck</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em>&nbsp;*type</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_TypeCheck" title="Permalink to this definition">¶</a></dt>
<dd><p>Return true if the object <em>o</em> is of type <em>type</em> or a subtype of <em>type</em>.  Both
parameters must be non-<em>NULL</em>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Length">
Py_ssize_t <code class="descname">PyObject_Length</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Length" title="Permalink to this definition">¶</a></dt>
<dt id="c.PyObject_Size">
Py_ssize_t <code class="descname">PyObject_Size</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Size" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-8">Return the length of object <em>o</em>.  If the object <em>o</em> provides either the sequence
and mapping protocols, the sequence length is returned.  On error, <code class="docutils literal"><span class="pre">-1</span></code> is
returned.  This is the equivalent to the Python expression <code class="docutils literal"><span class="pre">len(o)</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_LengthHint">
Py_ssize_t <code class="descname">PyObject_LengthHint</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, Py_ssize_t<em>&nbsp;default</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_LengthHint" title="Permalink to this definition">¶</a></dt>
<dd><p>Return an estimated length for the object <em>o</em>. First try to return its
actual length, then an estimate using <a class="reference internal" href="../reference/datamodel.html#object.__length_hint__" title="object.__length_hint__"><code class="xref py py-meth docutils literal"><span class="pre">__length_hint__()</span></code></a>, and
finally return the default value. On error return <code class="docutils literal"><span class="pre">-1</span></code>. This is the
equivalent to the Python expression <code class="docutils literal"><span class="pre">operator.length_hint(o,</span> <span class="pre">default)</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified">New in version 3.4.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GetItem">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetItem" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return element of <em>o</em> corresponding to the object <em>key</em> or <em>NULL</em> on failure.
This is the equivalent of the Python expression <code class="docutils literal"><span class="pre">o[key]</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_SetItem">
int <code class="descname">PyObject_SetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetItem" title="Permalink to this definition">¶</a></dt>
<dd><p>Map the object <em>key</em> to the value <em>v</em>.  Raise an exception and
return <code class="docutils literal"><span class="pre">-1</span></code> on failure; return <code class="docutils literal"><span class="pre">0</span></code> on success.  This is the
equivalent of the Python statement <code class="docutils literal"><span class="pre">o[key]</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_DelItem">
int <code class="descname">PyObject_DelItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelItem" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete the mapping for <em>key</em> from <em>o</em>.  Returns <code class="docutils literal"><span class="pre">-1</span></code> on failure. This is the
equivalent of the Python statement <code class="docutils literal"><span class="pre">del</span> <span class="pre">o[key]</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_Dir">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Dir</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Dir" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <code class="docutils literal"><span class="pre">dir(o)</span></code>, returning a (possibly
empty) list of strings appropriate for the object argument, or <em>NULL</em> if there
was an error.  If the argument is <em>NULL</em>, this is like the Python <code class="docutils literal"><span class="pre">dir()</span></code>,
returning the names of the current locals; in this case, if no execution frame
is active then <em>NULL</em> is returned but <a class="reference internal" href="exceptions.html#c.PyErr_Occurred" title="PyErr_Occurred"><code class="xref c c-func docutils literal"><span class="pre">PyErr_Occurred()</span></code></a> will return false.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyObject_GetIter">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetIter</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetIter" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <code class="docutils literal"><span class="pre">iter(o)</span></code>. It returns a new
iterator for the object argument, or the object  itself if the object is already
an iterator.  Raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal"><span class="pre">TypeError</span></code></a> and returns <em>NULL</em> if the object cannot be
iterated.</p>
</dd></dl>

</div>


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